megohmeters

[Pascone10]

ok well its ordered... well see.

[WhoIsThat?]

FWIW, for the price of two cups of coffee you can buy 100 ea., 10Meg, +/- 10%, resistors from Allelectronics or some such place and solder them in series to make a 1000 Meg, +/- 1%, calibration resistor. Shipping is extra $.

[xgfreon]

huh?

you said you needed a push to buy....i was pushing

[Pascone10]

FWIW, for the price of two cups of coffee you can buy 100 ea., 10Meg, +/- 10%, resistors from Allelectronics or some such place and solder them in series to make a 1000 Meg, +/- 1%, calibration resistor. Shipping is extra $.

ok explain how to do this please... i need 100 of the resisters? im a little lost.

[WhoIsThat?]

Here's a place to get the resistors
http://www.allelectronics.com/make-a.../4-WATT/1.html

100 of these wired in series gives 1000 Megohms, at a tighter tolerance than any single resistor.

This is probably cheaper than buying a single precision 1000 Meg ohm resistor, even if they sell them in QTY = 1, which I doubt. It might take you an hour to solder these up.

You'll need some kind of container to hold this composite resistor and you should probably seal the resistors with shellac or varnish to prevent changes in RH from changing its value.

With your meter's accuracy being +/- 3%, if you decide to buy a precision resistor to check your meter's calibration the accuracy of the resistor should be +/- 0.3% or better.

[Pascone10]

so i got this thing today....

am i using it wrong? i have one lead on the wire for run and one on the copper linset connecting the compressor. ( i know to get an accurate reading i need to go right to the compressor but i should still get a resistance reading with the wire no?

anyway this is not hooked up to anything just a unit in my garage..

i disconnected the compressor from the cap (single phase) and the meter beeps and flashes everyonce in a while a reading but not long enough to read it.... most of the time just reads 1

this is a 240v condensor. i megged on 250v and 500v......

also checked winding with FLUKE (lol) and extech ohms are similar and winding check out fine that way....

any ideas fellas?

[cuervo]

I also am in the market for a megohmeter and don't want to spend much. I found the Fieldpiece SMG5 for about $110. Here's a link to fieldpiece's manual I'm not sure if it will help you out with your meter.
Look at bottom right hand chart:
http://www.fieldpiece.com/Manuals/OpmanSMG5v08.pdf

Hope it helps. Let me know how yours is working out.

[DOGBOY]

so i got this thing today....

am i using it wrong? i have one lead on the wire for run and one on the copper linset connecting the compressor.

Are you serious?

[fcs]

Pascone10,

what do you think of the Extech ?

[Pascone10]

I like the extech to be honest. I mean you can tell its not a Fluke lol. It is durably ( is that a word?) Built. The only questionable thing is the insertion for the test leads.... Its a little on the loose side, however it still can develope a good reading... I would look into another extech in the future if I was looking for an inexpensive, not used everyday meter... I'm not sure about the scale tho so ill ask this.

In order to read higher then 200m ohms I need to be on the 1000v scale. I assume this is ok for 460 v units.. And when working on the smaller stuff I guess as long as I'm higher then 200m ohms its all good.. But I do like the meter so far.. Its also nice to have a multi meter built in, for ohm and voltage checks.. One more cool thing lol. You can see the actual battery reading of the meter when you go to VAC setting. I like that. I would buy another meter from them in the future tho!